If an object of mass 1 kg contains 4× 1020 atoms. If one electron is removed from every atom of the solid, the charge gained by the solid in 1 g is

Question

If an object of mass 1 kg contains 4× 1020 atoms. If one electron is removed from every atom of the solid, the charge gained by the solid in 1 g is (A) 2.8 C (B) 6.4 × 10-2 C (C) 3.6 × 10-3 C (D) 9.2 × 10-4 C

Tardigrade Admin · Accepted Answer

Here, number of electrons removed = number of atoms in 1 g or n=(4×1020/103)=4×1017 ∴ charge, q=n e = 4×1017×1.6×10-19 C=6.4×10-2 C

Q. If an object of mass $1 k g$ contains $4 \times 1 0^{20}$ atoms. If one electron is removed from every atom of the solid, the charge gained by the solid in $1 g$ is

$2.8 C$

$6.4 \times 1 0^{- 2} C$

$3.6 \times 1 0^{- 3} C$

$9.2 \times 1 0^{- 4} C$

Here,
number of electrons removed = number of atoms in $1 g$
or $n = \frac{4 \times 1 0 ^{20}}{1 0 ^{3}} = 4 \times 1 0^{17}$
$∴$ charge, $q = n e = 4 \times 1 0^{17} \times 1.6 \times 1 0^{- 19} C = 6.4 \times 1 0^{- 2} C$

Q. If an object of mass 1kg contains 4×1020 atoms. If one electron is removed from every atom of the solid, the charge gained by the solid in 1g is

2.8C

6.4×10−2C

3.6×10−3C

9.2×10−4C